The reason this card can be much better than Griselbrand is that with this out you can cycle through your entire deck till you find something you're looking for and it won't even cost you very much life.

Pay 1 life. Nope didn't find it.Pay 1 life. Nope.Pay 1 life. Nope.Pay 1 life. Oh there it is!

With Griselbrand, you can only draw in lots of 7 so you can't do that as easily.

@jfre81The reason they're broken isn't because they can be destroyed; it's that in destroying them your opponent responds by paying life, drawing cards, and winning next turn anyway. The only counters to this card are counterspells.

Combo cards like this aren't there to slowly increase your draw like a Dark Confidant, they explosively draw the top huge-amount of your library and allow you to win on the spot. The idea that this is balanced by enchantment removal implies that Ad Nauseam is better; which is hard to swallow. That card is awesome; but mostly because it's the best in the format at what it does; and not because it's a non-enchantment.

2) Ratings don't always mean that much. I mean, Necro is a 5/5 card no matter who you are; it broke the entire '96 Pro Tour. If it isn't rated 5, it's because new players who aren't used to the game (not saying they're n00bs or stupid or anything, just not familiar) aren't seeing the potential and have never read about Magic history.